This invention is in the field of raisable or liftable roofs for recreational vehicles to provide additional head room in the passenger compartment of the vehicle.
It has been proposed heretofore to provide roofs for recreational vehicles which can be lifted to provide additional head room within the vehicle when camping or the like. See, for example, the patent to Peterson et al. U.S. Pat. No. 3,212,813. In that patent, a roof structure is liftable and in so raising the same, side panels are swung upwardly or unfolded to provide additional sides extending upwardly from the vehicle to the raised roof. However, the structure described and shown in that patent involves fairly complicated manufacturing procedures, and results in a structure that is not completely weather tight. The patent to Borskey, U.S. Pat. No. 3,582,130 shows a liftable roof of rigid construction which, when lifted, extends canvass or other fabric sidewalls to provide sides thereof. The liftable roof is connected to the vehicle by crossed links pivoted at their intermediate portion, and each being slidable at its ends along the vehicle roof and the liftable roof. Such a structure, however, is not weatherproof and cannot be left in the raised position while traveling. The patent to Garrison, U.S. Pat. No. 3,463,541 discloses a liftable roof comprising rigid telescopically related sections, but the arrangement is such that the roof is considerably wider than the lower section, and thus the increased head room in the vehicle is not of maximum or most efficient width, and the sidewalls of the elevated portion taper downwardly and inwardly from the raised roof to the vehicle. Other patents of some pertinence to this invention are McKee, U.S. Pat. No. 3,802,732, Woods, U.S. Pat. No. 1,871,871, Orn et al. U.S. Pat. No. 3,145,046 and Cobb, U.S. Pat. No. 3,819,223. These additional patents, however, are subject to most of the same disadvantages pointed out with respect to the first three patents herein.